Ferro-concrete railway sleeper



Nov. 22, 1932. -r 7 1,888,287

FERRO-CONGRETE RAILWAY SLEEPER Filed Aug. 15, 1929 3 Sheets-Sheet 1 Nov;22, 1932. E. M. PROT FERRO-CONCRETE RAILWAY SLEEPER Filed Aug. 15, 19293 Sheets-Sheet 2 Z 721 FMZL Nov. 22, 1932.

E. M- PROT FERRO--CONCREITE RAILWAY SLEEPER Filed Aug. -15, 1929 3Sheets-Sheet 3 S. 777, pM'

Patented Nov. 22, 1932 UNITED STATES PATENT OFFICE ETIENNE MAROEL rRoT,or PARIS, FRANCE, ASSIGNQR ro soorE'rE A REsroNsA ILr'rE LIMITEE BITE:LA voIE EERBE' MODERNE, or PARIS, FRANCE FERRO-CONCRETE RAILWAY SLEEPERApplication filed August 15, 1929, Serial No. 385,996, and in FranceMarch 1, 1929.

For replacing wooden sleepers on rail ways, use has already been made offerroconcrete sleepers and, through habit, these latter have usuallybeen made in the shape of a parallels-piped as the first ones, so thatthe materials are not used in a rational manner.

On the other hand, the shape given to wooden sleepers and; which was theconsequence of the very nature of the material, of

its origin and of its working conditions, it it answered to the rationaltransmission of vertical stresses (provided use was made of a layer ofballast) answered rather badly to the condition of resistance tohorizontal stresses to which the track is subjected.

By giving to ferro-concrete sleepers a shape similar to that of woodensleepers, inconveniences inherent to these sleepers are met with, towhich is added that due to the very slight flexibility of ferro-concreteunder the unequal loads to which it is subjected, to

such an extent that it has been necessary, in certain existingferro-concrete sleepers, to provide special devices for increasing thisflexibility.

The present invention has for object a new type of ferro-concreterailway and tramway sleepers characterized by a high and recessed shapeand a wide sole portion so as to obtain a suitable distribution of theloads, a small unitary pressure on the ground and a rational use of thematerials.

The invention also consists in the following detail objects constituentof the inain object:

(a) The hollow vertical web of the sleepers terminates in divergent ribsabsorbing the horizontal stresses, the sleepers being embedded in theground. The horizontal 40 stresses are also transmitted to the ground bythe ribs of the inner face.

(6) The rails rest on the sleepers with interposition of a thickshock-absorbing wooden sole portion held in the sleeper and are securedon the latter by clips and bolts clampedon the sleeper by meansofresilient plates constituting unloosening devices.

('0)- The sleepers are recessed or hollowed out throughout their lengthor on one or more 150 portions of the latter.

The accompanying drawings illustrate, by way of example, a, form ofconstruction of the improved ferro-concrete sleeper iiraccordance withthe present invention.

Figure 1 is an elevation of this sleeper.

Figure 2 is a longitudinal section thereof.

Figure 3 is a plan. view of the same.

Figure 4 is a section made according to line IVIV of Fig. 1.

Figure 5 is a section made transversely to a track constructed withsleepers similar to that shown, in Figs. 1 we.

Figure 6 is a section made longitudinally to the said track.

Figure 7 is a longitudinal section, on an; enlarged scale, or thesleeper, showing how the rails are arranged on the sleeper.

Figures 8 and9 are respectively an elevation and a plan view of amodification: of this form of construction.

Figure 10is a sectional elevation of a modi fication comprising anarrangement allowing to secure in position double headed rails.

Figure 11 is a longitudinal section of a track equipped withsuchsleepers.

Referring to Figs. 1 to 7 the sleeper is constituted, in accordance withthe invention, by awide sole portion 1 having an upward extension formedby a recessed web 2, the side faces 3 of which terminate in divergentribs 4.

At the ends of the sole portion, the edges of thelatter terminate in ashape ensuring an equal resistance, as illustrated in Fig. 3, so. as tocause the materials constituting the sleeper to work in the bestconditions.

The shapeot the sleeper allows. to obtain,

under a reasonable weight, a resistance to vertical stresses so much themore great as the surfaceof the sole portion 1 is greater, and aresistance to side stresses also very satisfactory, owing to the factthat the sleeper is embedded in the ground, as shown in Figs. 5

and 6, and that the divergence of the ribs 4 prevents any sidedisplacement of the sleeper. The ribs 410 and lb of the lower facecontribute to transmit to the ground the horizontal stresses, which arethemselves transmitted to the sleeper through the rail.

The depth of the web 2 gives to the sleeper a great moment of inertia.

: cesses 11 pass bolts The recessed portion 6 of the web 2 allows toeasily arrange the bolts 5 for securing the rails, and at the same timeit reduces the weight of the sleeper (Fig. 7

The rails 8 respectively rest on a sole portion 7 made of a relativelyresilient material (oak impregnated with creosote or the like),relatively thick and which is held in a mortice 9 provided in a bulgedportion 10 which is formed on the sleeper opposite the passage of eachrail.

Opposite the mortice 9, the web 2 is provided with side ribs 17connected to the sole portion and to the web by curved portions andadapted to strengthen the said web at the place where the rails rest onthe same.

In the axis of the sleeper, on either side of the mortice, are providedrecesses 11 adjacent to the latter and in which are arranged clips 12for holding the rail and the wedges made of oak impregnated withcreosote, or any other resilient material 13 on which rest the clips 12.

Through the clips 12, wedges 13 and re- 5, the nuts 14: of whichdirectly bear against the clips 12, and the heads 15 of which fit uponthe upper inner face of the recessed web 2, with interposition of aresilient metal. plate 16.

This application of the bolt by both its faces on resilient membersallows to obtain a firm clamping and a very rigid securing in positionof the rails, thus avoiding any risk of unloosening and of spacing apartof the rails.

For preventing oxidation of the screw threads of the bolt extendingabove the nut and for the ease of removal, the nut can be a cap nut or ablind nut, or it can be covered with a pressed sheet-iron membercovering the nut and the top of the bolt, with interposition of tar orof any other similar material.

It is to be noted that the recessed shape of the sleeper, which might berecessed only at its end portions, allows the easy placing in positionand removal of the bolts, which can thus be readily replaced. Theattaching member which is not integral with the concrete and iscompletely independent of the same, can easily be electrically insulatedby simply coating with tar the metal parts and the concrete, or byinterposition of any suitable insulating material.

The arrangement of thick resilient sole portions under the rails allowsto obtain a very soft running.

The adjustment of the track, upon settling of the ground, can beeffected by packing, this adjustment can moreover be eifected, to acertain extent, by simply replacing the sole portions by sole portionsof greater thickness.

On the other hand, owing to the wide sole portion of the sleepers, whichallow the satisfactory distribution of the vertical stresses and thetransmission to the ground of a small unitary pressure, the use ofballast, can be dispensed with, the latter being, so to speak,incorporated, under a much more eflicient form, in the sleeper itself;the so-called tamping layer formed of choice materials, can at least bedispensed with and use ismade only of an under layer formed of sand orgravel, which is less costly.

In fact, the small pressure per square centimeter transmitted to theground by the wide bearing surface prevents the ground from beingpermanently unlevelled; as the ground is only resiliently distorted, thesleeper does not get out of the ballast, resulting in a better anchoringof the track and a reduced cost of maintenance.

Besides, the track equipped with sleepers which are in accordance withthe invention, embedded in the ground, has an extremely satisfactoryappearance, it is easy to run over,

to inspect and to maintain in a perfect condition of cleanliness.

Figures 8 and 9 illustrate a modification of the first form ofconstruction described, characterized in that the sleeper is narrower inits central portion.

This sleeper presents the same features and the same advantages as thepreceding sleeper.

In Figs. 10 and 11, are shown wedges 23, made of wood or similarmaterials, opposite the screw spikes 21 of the chair 22.

The placing of the wedge and its replacement in case of need areeffected with the greatest ease, through the recess, withoutnecessitating the removal of the sleeper from the track. As in theattaching member made entirely of metal, a member is provided whichpresses the rail on the sleeper and is ulled downwardly (the screwspike), as we 1 as a member bearing on the underside of the sleeper andpulled upwardly. This latter member, the wooden wedge, constitutes atthe same time the resilient member ensurin the permanence of theclamping. This attac ing member is cheaper than the attaching membermade entirely of metal, and it can be used in its place and stead in anycase; if it is considered as being not so safe and less perfect in thecase of the Vignole rail, it is, on

the other hand, to be recommended for securing the rail-chairs, thescrew spike being then ungble to incline as in the case of the footrai aIt is to be noted that the wooden wedge, which is moreover previouslycoated with tar, is practically sheltered from the action of moistureand weather conditions.

Owing to its recess, this latter sleeper, as the preceding sleepers, canbe very easily manipulated.

For loading and unloading it is easy to grasp it by means of two hooksfitting in the ends of the recess. For the placing in position and theadjustment, it is easy to manipulate it by inserting in the recess, ateach end, a lever of suitable shape and dimension.

It is to be understood that the forms of construction described havebeen given by way of example only, and that the number, shape, 6arrangement, nature and assemblage of the various parts can be modifiedin any suitable manner without departing from the scope of theinvention.

What I claim as my invention and desire 14) to secure by Letters Patentis A ferro-conorete railway sleeper including a relatively wide soleportion, an upward extension continuing therefrom in the form of ahollow web, divergent ribs between the ends 15 of the web and the soleportion, reinforcing and anti-creeping ribs on the under surface of thesole portion, rail seats provided on the upper surface of the web nearthe opposite ends thereof, additional ribs on opposite sides of the webbetween the seats and sole portion for reinforcing purposes, and thesole portion and its extension having a depth at least equal to that ofan ordinary timber sleeper increased by that of an ordinary layer ofballast and the sole portion having the value of at least double that ofan ordinary timber sleeper.

In testimony whereof I have signed this specification. ETIENNE MAROELPROT.

